Radiation dose-volume effects in the brain. Int J Radiat Oncol Biol Phys 2010 Mar 01;76(3 Suppl):S20-7
Date
03/05/2010Pubmed ID
20171513Pubmed Central ID
PMC3554255DOI
10.1016/j.ijrobp.2009.02.091Scopus ID
2-s2.0-76449114596 (requires institutional sign-in at Scopus site) 569 CitationsAbstract
We have reviewed the published data regarding radiotherapy (RT)-induced brain injury. Radiation necrosis appears a median of 1-2 years after RT; however, cognitive decline develops over many years. The incidence and severity is dose and volume dependent and can also be increased by chemotherapy, age, diabetes, and spatial factors. For fractionated RT with a fraction size of <2.5 Gy, an incidence of radiation necrosis of 5% and 10% is predicted to occur at a biologically effective dose of 120 Gy (range, 100-140) and 150 Gy (range, 140-170), respectively. For twice-daily fractionation, a steep increase in toxicity appears to occur when the biologically effective dose is >80 Gy. For large fraction sizes (>or=2.5 Gy), the incidence and severity of toxicity is unpredictable. For single fraction radiosurgery, a clear correlation has been demonstrated between the target size and the risk of adverse events. Substantial variation among different centers' reported outcomes have prevented us from making toxicity-risk predictions. Cognitive dysfunction in children is largely seen for whole brain doses of >or=18 Gy. No substantial evidence has shown that RT induces irreversible cognitive decline in adults within 4 years of RT.
Author List
Lawrence YR, Li XA, el Naqa I, Hahn CA, Marks LB, Merchant TE, Dicker APMESH terms used to index this publication - Major topics in bold
AdultAge Factors
Brain
Cognition Disorders
Cranial Irradiation
Dose-Response Relationship, Radiation
Humans
Models, Biological
Models, Theoretical
Necrosis
Radiation Tolerance
Radiosurgery